It has previously been proposed to determine the relative position of two shaft elements, which may both be stationary or rotating, with respect to each other by connecting concentric sleeves to respective shaft portions. Upon relative rotation of the respective shaft portions, for example due to torsion of the shaft upon being loaded by transmitting a substantial torque, or the like, the concentric sleeves will rotate with respect to each other. Electrical output signals can be obtained representative of the relative rotation of the sleeves.
The sleeves can be segmentally subdivided, in circumferential direction, into zones of high and low conductivity; they may be made, for example, of brass, bronze, or the like, and the zones of low electrical conductivity can be formed by cut-outs or air gaps in the circumferential portion, which can be left free or filled with a non-conducting material. Electrical current is induced in the sleeves by a winding surrounding the sleeves.